Genetic mechanisms of metabolic control and thermal sensing during thermoregulation. This research will significantly advance understanding of how animals can respond to climate change, and the results will benefit wildlife management processes. The proposed research will lead to collaboration with Prof. Ken Storey an ISI highly cited author and expert in microarray analysis. The cDNA microarray for Crocodylus porosus which I will construct in the proposed research will be a valuable resource ....Genetic mechanisms of metabolic control and thermal sensing during thermoregulation. This research will significantly advance understanding of how animals can respond to climate change, and the results will benefit wildlife management processes. The proposed research will lead to collaboration with Prof. Ken Storey an ISI highly cited author and expert in microarray analysis. The cDNA microarray for Crocodylus porosus which I will construct in the proposed research will be a valuable resource for Australia by increasing collaborations, and it will help find the cause of problems prevalent in the crocodile industry such as runt animals that significantly decrease production efficiency.Read moreRead less
Plasticity in placental vasculature and the evolution of viviparity in lizards. This cross-disciplinary research will provide thorough understanding of the reproductive physiology of animals with different forms of reproduction, information critical for conservation and management of Australia's biodiversity. Australia's unique reptiles provide the best animal system in the world for research in this area. Our research on maternal-embryonic interactions in this animal model has direct implicatio ....Plasticity in placental vasculature and the evolution of viviparity in lizards. This cross-disciplinary research will provide thorough understanding of the reproductive physiology of animals with different forms of reproduction, information critical for conservation and management of Australia's biodiversity. Australia's unique reptiles provide the best animal system in the world for research in this area. Our research on maternal-embryonic interactions in this animal model has direct implications for understanding some medical disorders, such as human angiogenic disorders. The research will strengthen ties internationally through research in South Africa, and provide training in combined biological and medical technologies. It will maintain Australia's long-term leadership in this area of research.Read moreRead less
Responses of reptiles to fluctuating thermal environments: behaviour or biochemistry? I propose a conceptual shift in the way thermal physiology of reptiles is interpreted, questioning the predominant role of behaviour in reptilian thermoregulation. I will test the hypothesis that changes in cellular biochemistry are an important mechanism by which reptiles respond to environmental fluctuations. I will determine the relationship between metabolic enzyme activity and performance functions, and ....Responses of reptiles to fluctuating thermal environments: behaviour or biochemistry? I propose a conceptual shift in the way thermal physiology of reptiles is interpreted, questioning the predominant role of behaviour in reptilian thermoregulation. I will test the hypothesis that changes in cellular biochemistry are an important mechanism by which reptiles respond to environmental fluctuations. I will determine the relationship between metabolic enzyme activity and performance functions, and the results may call for a re-assessment of current concepts such as the notion that reptiles must achieve "preferred" body temperatures to maintain performance.Read moreRead less
Design of the cardiovascular system of living and fossil vertebrates. This project aims to understand how the heart and blood vessels evolved in mammals, birds, reptiles and fish to achieve efficiency. The heart is the most important organ for life. The project will study the structure and function of vertebrate animals’ hollow and spongy hearts to show how energetics shaped their evolution. It will measure arterial holes in bone to gauge brain and bone metabolism, which opens up a new way to me ....Design of the cardiovascular system of living and fossil vertebrates. This project aims to understand how the heart and blood vessels evolved in mammals, birds, reptiles and fish to achieve efficiency. The heart is the most important organ for life. The project will study the structure and function of vertebrate animals’ hollow and spongy hearts to show how energetics shaped their evolution. It will measure arterial holes in bone to gauge brain and bone metabolism, which opens up a new way to measure metabolism in extinct animals directly from fossils, rather than by inference from living relatives. The expected outcome is to correlate cardiovascular design and metabolic rates of organs.Read moreRead less
The physiological mechanisms underlying animal group dynamics. The project aims to provide novel insights into how individual differences in muscle biomechanics and metabolism constrain group assemblages, and the extent to which these constraints can cause fission and fusion of populations in changing environments. This research is significant because most ecological and evolutionary processes and their management occur at the level of groups. The project expects to yield a theoretical model cal ....The physiological mechanisms underlying animal group dynamics. The project aims to provide novel insights into how individual differences in muscle biomechanics and metabolism constrain group assemblages, and the extent to which these constraints can cause fission and fusion of populations in changing environments. This research is significant because most ecological and evolutionary processes and their management occur at the level of groups. The project expects to yield a theoretical model calibrated against empirical data to predict group dynamics of natural populations in changing environments, and of human crowds as diseases and lifestyle change physiological capacities.Read moreRead less
Does testosterone produce duds or studs? A performance-based examination of the Immunocompetence Handicap Hypothesis. The evolutionary persistence of testosterone (T) as a vertebrate reproductive hormone is viewed as a double-edged sword. On the one hand T secretion is required for development and expression of appropriate reproductive functions. On the other hand T is known to suppress immune functions and is thus considered a liability to male health. We are examining an alternate hypothesis: ....Does testosterone produce duds or studs? A performance-based examination of the Immunocompetence Handicap Hypothesis. The evolutionary persistence of testosterone (T) as a vertebrate reproductive hormone is viewed as a double-edged sword. On the one hand T secretion is required for development and expression of appropriate reproductive functions. On the other hand T is known to suppress immune functions and is thus considered a liability to male health. We are examining an alternate hypothesis: that T-induced immunosuppression benefits breeding males by protecting their physical performance levels during immune challenge. We will examine this hypothesis by quantifying the interactive effects of T and immune challenge on the aerobic capacity of male birds.Read moreRead less
Does physiological plasticity of individuals render populations resilient to climate change? Abrupt environmental changes can put natural populations at risk of extinction. The project will show to what extent individuals can compensate for temperature changes and thereby render populations resilient to climate change. This research will make theoretical advances and improve the power to predict impacts of future climate change.
Evolution of viviparity in reptiles: the fundamental role of junctional complexes. This project utilises unique Australian reptile fauna to understand global questions in fundamental biology. We will discover basic biological information on native species, which will be important in future conservation of Australian ecosystems and animals and ultimately in helping to maintain Australia's biodiversity. The project also provides training opportunities for graduate and undergraduate students in ....Evolution of viviparity in reptiles: the fundamental role of junctional complexes. This project utilises unique Australian reptile fauna to understand global questions in fundamental biology. We will discover basic biological information on native species, which will be important in future conservation of Australian ecosystems and animals and ultimately in helping to maintain Australia's biodiversity. The project also provides training opportunities for graduate and undergraduate students in several different research methods that are widely applicable in the more general Australian workforce. Because the research work is genuinely cross-disciplinary research, its findings are applicable to both biological and medically oriented technologies.Read moreRead less
Determinants of metabolic rate in animals. The metabolic rate of an animal represents its fundamental "cost of living" and varies dramatically (>100-fold) between different vertebrate species. We have proposed the "membrane pacemaker theory" to explain this variation and currently this is the only mechanistic explanation of metabolic variation between species. It has received significant international interest. A species metabolic rate and its maximum lifespan are connected but the precise mecha ....Determinants of metabolic rate in animals. The metabolic rate of an animal represents its fundamental "cost of living" and varies dramatically (>100-fold) between different vertebrate species. We have proposed the "membrane pacemaker theory" to explain this variation and currently this is the only mechanistic explanation of metabolic variation between species. It has received significant international interest. A species metabolic rate and its maximum lifespan are connected but the precise mechanistic link between them is unknown. We will investigate the mechanisms underlying the "membrane pacemaker theory" as an explanation of the metabolic rates of vertebrate species and its role in the determination of maximum lifespan.Read moreRead less
Uterodomes and the evolution of viviparity. We will test the hypothesis that uterodomes, which are cell structures unique to the early pregnant uterus in mammals, and the cellular changes accompanying their development, are essential to the evolution of viviparity in amniotes. The proposal stems from our recent discovery that uterodomes develop in the uteri of viviparous lizards as well as in mammals, suggesting key commonalities at the cellular level in the evolution of live birth across amnio ....Uterodomes and the evolution of viviparity. We will test the hypothesis that uterodomes, which are cell structures unique to the early pregnant uterus in mammals, and the cellular changes accompanying their development, are essential to the evolution of viviparity in amniotes. The proposal stems from our recent discovery that uterodomes develop in the uteri of viviparous lizards as well as in mammals, suggesting key commonalities at the cellular level in the evolution of live birth across amniote vertebrates. We will take advantage of the unique combination of placental types among Australian lizards, including a species with both oviparous and viviparous populations.Read moreRead less